Toward a multifunctional nature-based coastal defense: a review of the interaction between beach nourishment and ecological restoration

Coastal protection has evolved from focusing on hard solutions such as breakwaters and groynes to include soft or nature-based solutions (NbS). NbS have been proposed as cost-effective means to offer long-term coastal protection and at the same time strengthen coastal resilience and biodiversity. However, projects utilizing NbS for coastal protection have often focused on a single solution and the evidence of improved biodiversity remain equivocal. In this paper, we review solutions traditionally used for disparate purposes - namely beach nourishment and the establishment of vascular plants such as seagrass and dune grass. The main incentives behind large-scale beach nourishment projects are often the cost-effectiveness, multifunctionality and dynamic shoreline protection whereas the focus of vegetation restoration has typically been on recreating important habitats and not specifically as a coastal protection measure. Based on previous studies and an on-going large-scale coastal adaptation project in southern Sweden, we investigate the feasibility of combining these seemingly dichotomous management strategies to yield a viable physical defense and at the same time strengthen coastal biodiversity and ecosystem multifunctionality. Given the urgency in combatting biodiversity loss and adapting to a changing climate, management interventions for coastal protection should explicitly incorporate ecological values into every coastal protection measure and seek innovative, integrated approaches that consider both geomorphological and ecological values and the possible complementarity between the two.

Automated summary

Coastal protection has shifted from hard solutions to soft or nature-based solutions (NbS) which offer long-term protection and enhance resilience and biodiversity. However, previous projects focusing on single NbS solutions have shown mixed results in terms of biodiversity improvement. This study explores the potential of combining traditional approaches like beach nourishment with vegetation restoration to achieve both coastal defense and enhanced biodiversity.